Ohio Network of American History Research Centers

From Ancestry.com Wiki

Established in 1970 to aid in the collection, preservation, and accessibility of research materials related to Ohio history, the network is composed of seven institutions—Ohio’s two largest historical societies and five state universities. A central feature of the network is the division of the entire state into seven distinct geographical areas for research. Each center also collects county records for its area, but the amount of material available may vary greatly from county to county.